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Quarterly Information - Summary of Quarterly Information (Parenthetical) (Detail) - $ / shares
3 Months Ended 12 Months Ended
Dec. 31, 2020
Sep. 25, 2020
Jun. 26, 2020
Mar. 27, 2020
Dec. 31, 2019
Sep. 27, 2019
Jun. 28, 2019
Mar. 29, 2019
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Selected Quarterly Financial Information [Abstract]                      
Limited partnership interest value $ 1,000 $ 1,000 $ 1,000 $ 1,000 $ 1,000 $ 1,000 $ 1,000 $ 1,000 $ 1,000 $ 1,000 $ 1,000